isaac coming up a bit later in the broadcast. >>> president barack obama began his road to charlotte tour today as he heads toward next week's democratic national convention. from the next four days he'll campaign in battleground states as well as visit the hurricane ravaged gulf coast. the challenger, gop presidential candidate mitt romney also campaigning in the battleground states. hoping to keep the momentum from last week's republican national convention. drew levinson reports both men took jabs at one another out on the campaign trail today. >> reporter: president barack obama went to iowa. the state which four years ago propelled him to the white house. [ cheering and applause ] the president mocked what was said at the republican national convention. >> let me recap it for you. everything that's bad, it's obama's fault. and governor romney is the only one who knows the secret to creating jobs and growing the economy. >> reporter: he told the crowd there's more work to do when it comes to jobs, energy, and education. >> we've got for doors of opportunity to open to every singl